Regulating system



March 19, 1929. HULL 1,706,164

REGULATING SYSTEM Fil ed Nov. 6, 1925 Inventor: JOhT'W I. H ULL,

His Attorneg.

Patented Mar. 19, 1929.

UNITED STATES PAT JOHN L HULL, 0F SCHENECTADY NEW IQ'ORK, ASSIGNOR1,706,164 ENT OFFICE.

COMPANY, A CORPORATION OF NEW YORK.

REGULATING SY STEM.

Application filed November 6, 1925. Serial- No. 67,472.

chine are driven by electric motors it is essential that the speed of amotor driven roll be varied in accordance with the cloth passing over'such roll, or if the cloth is being rolled up thereby, it is essentialthat the speed be such as to roll the cloth up at the rate of feed.:' Inany such installation it is very desirable that the speed control systemshall be as free from hunting as 7 possible since hunting introduceslosses and non-uniformity in the product, and it is the primary objectof my invention to provide aregulating system which shall besubstantially free from hunting.

The features of my invention which are I believed to be novel andpatentable will be I pointed out in the appended claims. Fora betterunderstanding of my invention, reference is made in the followingdescription to the'accompanying drawings in which F1g-. 1

is a diagrammatic representation of my invention as applied to thecontrol of amotor driven part of a textile mill; Figs. 2 and 3 show.different positions of the switch mechanism; and Fig. 4 represents thepreferred form of the -anti-hunting switch which is diagrammaticallyrepresented in Fig. 1.

In Fig.1 .there is represented apparatus for rolling up a sheet offabric 10 as it is manufactured. I The motor llvfor driving thewinding-up roll 12 ishere represented as an alternating-currentcommutator motor of a variable speed type, the speed .being varied byshifting the brushes on the commutator. Such a motor is described inReissue Patent No. 14,031 to Schrage. A reversible pilot motorrepresented at 13 is provided for shifting'the brush yokes 15' of themotor 11 through suitable gearing represented at 14. The pilotmotor isprovided with two field windings 16 and 17 and it will be understood that when' the motor 13 is energized through one field winding 17, it willoperate to shift the brushes of the motor 11 in such a direction as tolower its speed and when the motor 13 is energized through the otherfield winding 16, it will shift the brushes of motor 11 in the oppositedirection to raise its speed. The control of the pilot motor 13 is bymeansjof the switch mechanism repre .upon which rests a hollow rack 27,

sented at 18 in accordance with the rate of feed of'the fabrid 10. Thefabric 10 passes through what is known in the textile industry as acompensating gate, comprising a compensating roll 20 which is free tomove up and down in a guiding frame 19. The weight of the roll 20 may bepartially balanced by acounterweight 21, such that the 'roll 2O keepsthe fabric tight without undue strain, and raises and lowers asthe feedvaries with respect to the rate at which the fabric 1s rolled up at 12.The weight 21 1s secured to a chain 22, which passes over a sprocket 23on a shaft 24 on the top of the frame and is then secured to theslidable bearing 25 of the roll 20. The opposite side of the frame atthe other end of' the roll 20 is similarly arranged. The up and downmovement of the roll 20 serves to operate the switching device 18 in themanner. hereinafter described.

A preferred form of the switching device 18 isshown in Fig. 4, but forthe purpose of better illustrating the principle of the invention, amore diagrammatic form of the switch is shown in Fig. 1. In Fig. 1 theswitch 18 comprises a supporting base'26 geared to a pinion 28, a doubleended contact rod 29 free to slide between its head pieces 30 and 30'through the hollow rack 27, contacts 31 and 31 placed in alinement withthe opposite ends of the contact rod 29 and springs 32 and 32' to whichcontacts 31 and 4 31 are secured.

The sliding connection between rod 29 'and the hollow rack 27 developsenough TO GENERAL ELECTRIC cooperating contact.

retaining chambers 40 and 40 and the springs press the contacts againstthe inner ends of these chambers with more force than that required toslide rod 29 in rack 27 so that said springs are not further compresseduntilthe rod 29' reaches the limit of its frictional travel through therack 27 as determined one of the enlarged heads of said rod comingagainst an 'end of the rack, as shown in Fig. 2.

The pinion 28 is secured through a shaft 83 to' a chain wheel 34andthewheel 34 is connected to another chain wheel 35 secured toshaft24: by means of the chain 36. The chain 36 passes over an idle chainwheel or pulley 37 which is free to rotate on a cam 38 driven from anysuitable part of the mill so as to give the switch rack 27 anoscillatory motion in addition to any motion imparted to it by thevertical movement of the roll 20. The chain 36 is held tight by weights39 and 39 so as to eliminate lost motion. As the motion of thecam 38alternatel increases and decreases the length of the c ain between chainwheels 35 and 34, the rack 27 is given the oscillatory motion abovereferred to and weight 39 thus also has an up and down movement inaddition to any movement imparted to it by the vertical movement of roll20.

When rack 27 moves to the right due to a lowering of roll 20, rod 29will move with it due to friction between the rod 29 and rack 27 until.contact' is made between 30 and 31. "At this time one or more briefmomentary contacts will be made because of the oscillatory motion andbecause as soon as contact is made, rod 29 will slide to the left withrespect to the rack; The duration of contact will increase with the rateof movement of the roll 20 and thus for every revolution of cam 38 theratio of the time that the contact is closed to the time it is contact31 at the extreme part of. the .oscillatory movement. The pilot motor 16will give a final fine adjustment of the brushes such as to cause roll20 to cease its motion altogether, or perhaps to rise very slowly,

and rack 27 to creep slowly to the left until such time as the reverseoperation takes place at contacts 30 and 31'. Let us suppose how- .everthat due to a larger discrepancy in speed the roll 20 descends stillfurther than that assumed above; rod 29 will be moved through rack 27until contact head piece 30 abuts against the. end of the. rack. Now theoscillatory movement commences to compress spring 32 instead of moving,rod 29 through the rack and the duration of'contact becomes longer,increasing the speed corrective operation of the pilot motor. Finally,when the spring is sufiicie'ntly compressed, the contact 31 will followthe contact 30 back and forth and the pilot motor circuit will remainclosed continuously giving the maximum corrective' operation to thepilot motor and mosses paratively rapid rate. This condition of theswitch is represented in Fig. 2. The reverse operation takes place incase the maximum correction in the opposite direction is necessary.

The central position of the switch parts 18 corresponds to the centralposition of the roll 20. It will appear, however, that after a partialor maximum correcting operation such as has been just described, the rod29 no longer will be in a central position with respect to the rack 27and roll 20, but will be moved through the rack away from the contact31,as shown for example, in Fig. 3. This is an important advantage becauseordinarily after a maximum corrective operation the motor 11 will beleft runnin too slow or too fast; in the case described, too

fast. It will therefore be desirable to start slowing down the motorgradually even betion and that is what happens. Furthermore, the.momentary corrective contact period is now increased to thatcorresponding to the maximumdistance which rod 29 can move through rack27 so that the correction necessary to slow down the motor isanticipated by the device and is gradually applied in proportion to theneed. The nature of the correction applied is therefore also dependentupon the recent past performance of the device.

In certain cases the oscillatory motion furnished by the cam 38 can beomitted since it will be evident that the'essential principles involvedwhich accomplish a correction in speed in proportion,.to'its need andanticiates the need in time to prevent anything ut a slow hunting actionwill still exist without the oscillatory motion. Where this jmotion isomitted the shifting of the brushes continues at full speed until themotion of the gate is actually slightly reversedand the inertia of thepilot motor thus offers an over-correction. The addition of theoscillatory motion improves the action by moving the pilot motor butslowly when roll 20 is moving slowly, and moving it rapidly withrapid'moveme'nt of roll 20 and permits the omission of the usual pilotmotor brake as well as more completely eliminating the hunting. i

It has been demonstrated that the relative proportions of the variousparts of the apparatus may be so chosen as to result in a practically neligible amount of hunting and crawling of the variable, in thisv casethe vertical movement of the roll 20.

In practice the switch mechanism is built more compactly than that abovedescribed and is placed in a box to keep out-dirt and moisture. Thepreferred design takes the form shown in Fig. 4. s

In Fig. 4:, '34 represents the chain wheel lar 44 secured to shaft 38and the hub by means of a compression spring 46. However, if restrainedthey can slip on shaft 38. Between sleeves 42 and contact piece 43 is atorsional sprlng 47 having its ends engaging pins 49 and secured incollar 42 and gether,

contact piece respectively, in such a way that these parts willordinarily turn tobutif contact piece 43 is held stationary and collar42 is moved by reason of dog: 56 coming in contact with finger 41,

relative movement will occur between c0llar 42 and contact piece 43.Spring 47 is finder, sufiicient initial torsional strain to preventrelative motion of 42 and 43 even with 43 restrained, and with 43sliding on friction collar 44 until positive motion is imparted'to 42 byengagement of the dog 56 and the collar 42/ Contact piece 43 carriescontact fingers 51 and 51 on either side which cooperate with stationarycontact fingers 52 and 52 to close a circuit between 52 and 52 andthrough them the circuit of the pilot motor for the desired direction ofrotation. Preferably stop fingers 53 and- 53' are prfi ijided to-limitthe movement without placing excessivestrain on the contact fingers 522111(1'252. .Although the parts of this switch mechanism arearrangeddifi'erently rthan diagrammatically represented in Figs. 1 to 3,it will be evident that it is designed to perform the same functions aspreviously described. In .Fig. 4 the switch mechanism is represented ina central position with the contacts open; Ifthe wheel 534 and shaft 38are rotated in a counterclockwise direction facing the wheel 34,

parts 42 and 43'will move with them due to :2

the frictional engagement until contact fingers' 51 and 51 come againstcontacts 52 and 52 Upon further movement parts 42 and 43 will slip onshaft 38 until dog 56 eventually comes against finger 41., Upon Surthermovement-of shaft 38 inthe'same irection, sleeve 42 willbeturned with itand place spring 47 under tension thereby maintaining" contacts 51 and52 closedcontinuously. Now when the shaft is rotated in the 'oppositedirection, contact. piece '43 will remain stationary, or substantiallyso,

until the spring 47 is unwound to its initial position where .pins 49and 50 are in a radial line. .Then both sleeve 42 and contact shaft byfriction until the contact finger on -the opposite side .(not shown)comes in contact with its stationary contact and the parts 42 and 43will start to slip. This slipping will continue until the shaft stopsrotating, or until the dog 56 comes against a finger on sleeve 42 (notshown) diametrically opposite finger 41. It will be noticed that contact52 is carried on a "spring finger 54. This makes certain a circuitbetween 52 and 52 as with solid contacts it would be very difiicult toobtain simultaneous contact between 51 and 52 and also between 51 and52.

While I have described certain specific embodiments and applications ofmy invention, I do not wish to be limited thereto, but seek .to cover inthe appended claims all embodiments and applications of my inventioncoming fairly within the true scope thereof. lVhat I claim as newanddesire to secure byLetters Patent of the United States is 1. In aspeedcontrol system, a motor, acontinuous material subject to a constantor variable rate of feed acted upon by said 1110- tor, and means forcont-rolling the speed of said motor in accordance with the rate of feedof said material comprising a gauging device moved in response to thedifference between the rate of feed of said material and the rate it isacted upon by said motor, speed regulating means for said motorcontrolled by the movement of said gauging device, and means forimposing a continuous oscillatory movement on the controlling action ofsaid gauging device. I

2. Means for regulating the speed of a motordriven textile roll inaccordance with the rate of feed of the textile material comprising agauging device movable in oppos te directions in accordance withincreasing and decreasing slack 1n the material operated upon by theroll, an'electric motor for driving said roll, a speed controller forsaid metor, and means operating upon said speed controller in responseto the position and rate of-movement of said gauging device forprogressively correcting the speed of said motor in proportion tovariations from a predetermined amount of slack in said material and inproportion to the rate of change in such slack.

z 3. In a motor' drive installation where a motor operates upon acontinuous material which is subject to a variable rate of feed,

means for controlling the speed of said motor comprising a gaugingdevice moved in opposite directions in response to slow .and fast ratesof feed-of said material as compared-to the rate at which said motoroperates thereon, a switching device having av central non-regulatingrange of movementm'ovable in opposite directions beyondsaidnon-regulating range for respectively increasing and decreasingthespeed of said motor, a driving connection between said gauging andswitching devices having a central range of movement where the drive 5is through frictional slipping parts and having extreme r'angesofmovement where the drive is through resilient positive drivingconnections.

4. In a motor drive installation where a 11) motor operates upon acontinuous material which is subject to a variablerate of feed, meansfor controlling the speed of said motor comprising a gauging devicemoved in opposite directions in response to slow 15 and fast rates offeed of said material as compared to the rate which it is acted upon bysaid motor, a regulating device for said motor having a centralnon-regulating range of movement movable in opposite directions beyondsaidnon-regulating range for respectively increasing and decreasing thespeed of said motor, a driving connection between said gauging andregulating devices having a central range of movement where the drive isthrough frictional slipping parts and hav-- ing extreme ranges ofmovement where the drive is through resilient positive drivingconnections, and means for imposing a continuous oscillatorymovementjupon the regulat-ing action of said gauging device.

5. In a speed control system wherein a motor operates upon a continuousmaterial which is subject to a variable rate of feed, a gauging devicemovable in opposite directions in response to slow and fast feeds ofsaid material as compared to the rate at -which said motor operates onsaid material, an electric contactor arranged to be moved in oppositedirections for respectively increasing and decreasing the speed of saidmotor, said contactor having a freely movable central non-regulatingrange of movement, driving means for said contactor] moved in accordancewith the movement ,of

said gauging device, a combined frictional and resilient drivingconnection between said driving means and contactor which permits apositive frictional drive within the freelymo'vable non-regulating rangeof said contactor, relative slipping between said driving means andcontactor when the ganging device is moving through a central range andthe contactor has been moved to a regulating position and a resilientpositive drive $5 for extreme movements of said gauging device.

6. A regulating device comprising a contactor movable in oppositedirections to make contact with cooperating relatively stationarycontacts for respectively produc ing opposite regulating effects, saidcontact tor having a freely movable non-regulating range between saidcontacts, gauging means movable in opposite directions in re- 5 sponseto opposite regulating requirements mosses for operating said contactor,means for continuously imposing a slight oscillatory movement upon theregulating movement of said gauging means, and a frictional drivingconnection between said gauging means and contactor which permits saidcontactor to be moved against either cooperating contact and then toslip with respect to the gauging device, so that the combined movementof the gauging device and continuous oscillatory movement produces aregulation proportional to the rate of movement of said gauging device.v

7. A regulating device comprising a contactor. movable in oppositedirections to make contact with relatively stationary contacts toproduce opposite regulating effects, said contactor having a freelymovable nonregulating range, a gauging device movable in oppositedirections in response to opposite regulating requirements for movingsaid contactor, a frictional driving connection between said gaugingdevice and contactor which permits positive movement of said contactorby said gauging device within the freely movable non-regulating rangebut which permits the contactor to slip with respect to the gaugingdevice when it comes against said relatively stationary cooperatingcontacts, whereby after such regulating operation the gauging device isdisplaced with respect to the contactor substantially in proportion tothe extent of the regulation.

8. In a speed control system, a motor, a contlnuous material subject toa ,eonstant or variable rate of -feed acted upon by said motor, andmeans for controlling the speed of said motor in accordance with therate of feed of said material comprising a gauging device moved inopposite directions in response to plus and minus and minusdifferencesbetween the rate of feed of said material and the rate it is acted uponby said motor, speed regulating means for said motor controlled by saidgauging device, and means associated with said gauging device wherebythe speed regulating action of said device 18 suspended as soon asthedirection of motion of the device reverses while in a central portion ofthe travel of said device and whereby the speed regulating action ofsaid device remains continuous without regard to a reversal in itsdirection of movement in zones of travel of the device outside theaforesaid central portion.

9. In a speed control system, a motor, a continuous material subject toa constant or variable rate of feed acted upon by said motor, and meansfor controlling the speed of said motor inaccordance with the rate offeed of said material comprising a gauging device moved in response to adifference between the rate ofvfeed of said material and the rate it isacted upon by said motor, speed regulating means for said motorcontrolled by said gauging device, and means associated with sa1dgauging device for making the 10. In a speed control system, a motor, a

continuous material subject to a constant or variable rate of feed actedupon by said motor, and'means for controlling the speed of said motor inaccordance with the rate of feed of said material comprising'a gaugingdevice moved in opposite directions in response to his and minusdifferences between the rateoi feed of said material and the rate it isacted upon by said motor, speed regulating means for said motorcontrolled by said gauging device, and means associated with saidgauging device for making the speed controllin actionthereof dependentupon the rate 0? motion of said device, reducing it to zero when themotion of the gauging device stops while it is in a central portion ofits range of travel, but permitting a maximum speed .re ating action ofsaid device without regar to its rate of motion when it is in zones oftravel outside the aforesaid central portion.

In witness whereof, I have hereunto set my hand this 5th day ofNovember, 1925.

J OHN I. HULL.

